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Chapter 9
Evaluation of Gait
Introduction
Gait Analysis – functional evaluation of a
person’s walking or running style
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Systematic method of identifying specific
deviations in the gait pattern and determining
their cause and implications
Goals of analysis vary
Introduction
Dysfunctional or antalgic gait can arise
from acute or chronic injury or improper
biomechanics
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Prohibits normal weight-bearing
Influences stresses placed on joint surfaces
Predisposes patient to additional injury
Rehabilitation and/or correction of
biomechanics
Observation Techniques
Process of gathering, organizing, and
interpreting sensory information
Observation best obtained by using stopaction video
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Video can be slowed down and replayed
Permanent record on file
Limb position, ROM, speed of motion, force
production, timing of events in gait cycle
Observation Techniques
Treadmills
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Pros and cons
Stride length
Guidelines for observational gait analysis
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Page 304
Auditory information (cadence)
Correlate findings with orthopedic and
postural evaluations
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Figure 9-2, pages 305-306
Gait Cycle
Represents the combined function of the
lower extremity, pelvis, and spinal column
Walking – cyclical motion, bipedal
Center of gravity
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Easily displaced in the desired direction
Positioned high, second sacral segment
Greater portion of body weight is located in
trunk, head, and shoulders
Figure 9-3, page 307
Gait Cycle
Components of normal walking gait do not
transfer to most athletic activities
Specific to the motion:
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Force distribution across the foot, muscle
actions, joint motions, and center of gravity
Normal Gait
Normal cadence = 107 (+ 2.7) steps per
minute
Normal stride length = 75 (+ 1.6) cm
Symmetrical and uninterrupted rhythm
Terminology – Table 9-1, page 307
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Rancho Los Amigos
Normal Gait
Affected by intrinsic factors
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Joint ROM
Muscle strength
Body type
Gender
Affected by extrinsic factors
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Incline of surface
Surface type
footwear
Gait Phases
Stance Phase
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Initial contact of heel until toe breaks contact
with surface (toe-off)
Swing Phase
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Between toe-off and next initial contact
Open kinetic chain, non-weight bearing
Limb repositions itself
Figure 9-4, page 308
Gait Phases
During walking – one leg is in stance
phase while the other leg is in the swing
phase
Efficient walking
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Minimal upward and side-to-side motion
Maximal forward motion
Rotation of pelvis in transverse plane adds to
step length
Stance Phase
60% of gait cycle
Closed kinetic chain during weightbearing, allows forces from lower extremity
to be transmitted to ground, producing
movement
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Leg decelerates just before initial contact,
preventing injury to heel
Enables balance and push off
Stance Phase
5 distinct periods:
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Initial contact
Loading response
midstance
terminal stance
Preswing
Box 9-1, pages 310-311
Initial Contact
Begins with foot touching surface
Contact should be through lateral aspect
of plantar surface
Opposite limb is ending with toe-off
Subtalar joint – supinated @ 5 degrees
Talocrural joint – dorsiflexed
Both limbs in contact with surface
Loading Response
Response to absorption of body weight by
initiating flattening of the foot
Subtalar joint – pronates
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Unlocks midtarsal joints, allowing foot to
become flexible
Tibial internal rotation – increased medial
forces at foot, leg, knee
Talocrural joint – plantarflexes
Loading Response
Muscle support – decelerates pronation
and plantarflexion
Hip remains flexed
Period lasts until double limb support has
ended
Midstance
Begins as body weight moves over
stationary support limb and ends when
center of gravity is directly over the foot
Subtalar joint – supinates
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Locks midtarsal joints, makes foot a rigid lever
Preparing for efficiency during propulsion
Talocrural joint – dorsiflexes
Hip moves into extension
Terminal Stance
Starts as center of gravity passes over the
foot and ends just before the contralateral
limb makes contact with the ground
Body moves forward with weight shifting
over metatarsal heads until contralateral
limb provides new base of support
Toes extended, tibia externally rotated
Subtalar joint – supinated
Hip and knee continue to flex
Preswing
Transitional period of double support
Limb is uploaded and prepared to swing
Begins with initial contact of contralateral
limb and ends with toe-off of stance limb
Swing Phase
Begins as soon as the toes leave the
surface and terminates when the limb next
makes contact with the surface
Gravity assists in pulling leg mass down
Momentum gained at toe-ff helps carry leg
through the swing phase
Three periods
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Initial swing, midswing, terminal swing
Box 9-2, pages 312-313
Initial Swing
Begins at the point where toes leave the
ground and continues until knee reaches
its maximum range of flexion (@ 60O)
Femur advances
Ankle dorsiflexes, allowing toe clearance
Subtalar joint - pronation
Midswing
Knee extends until tibia is vertical to
surface
Thigh continues to advance, toe clearance
is ensured, propulsion continues
Talocrural joint – dorsiflexed to neutral or
slight dorsiflexion
Terminal Swing
Occurs from end of midswing to initial
contact period of the stance phase
Trunk is erect
Thigh decelerates for heel contact
Knee extends to create step length for
heel contact
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Step length – distance traveled between initial
contacts of right and left foot
Subtalar joint - supination
Qualitative Observation of Gait
Rise and fall of the body in vertical
direction = 5cm
Path of center of gravity is sinusoidal or a
smooth curve
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No sharp braking
As speed increase, arm action is involved
Questions to address during gait analysis
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Page 309
Running Gait
Series of smoothly coordinated jumps
executed from one foot to the other foot
Purpose – to move body from one position
to another at a moderate to fast speed
As speed increase – techniques changes
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Arm swing ROM, stride length, cadence, and
knee flexion ROM
Running Gait
Muscular force and speed of contraction
also change
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Control pronation during loading response
and initiate supination prior to preswing
Walking versus Running Gait
2 distinct differences:
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Flight phase – neither foot is in contact with
the ground
At no time are both feet in contact with the
surface at the same time
Stance phase
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Walking – 62% of the cycle; Running – 33% of
the cycle
Same joints used
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Differences in degrees of motion and timing of
actions
Figure 9-5, page 314
Ground Reaction Forces
Every contact of the foot with the surface
generates an upward reaction force
GRFs are measured and compared
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Figure 9-6, page 315
Vertical component of GRF during running is
2 to 3 times the runner’s body weight
Classified as rearfoot, midfoot, or forefoot
strikers
Ground Reaction Forces
Factors influencing GRF patterns:
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Running speed
Running style
Ground surface
Grade of incline
Shoes/orthotics
Questions to address during observation
of running gait
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Page 315
Pathologies Affecting the Gait
Cycle
Box 9-3, page 316
Table 9-2, page 317
Acute Lower Extremity Strains and
Sprains
Overuse Injuries
Leg Length Discrepancies
Functional Bracing